[llvm] [DebugInfo] Enable deprecation of iterator-insertion methods (PR #102608)

[Nikita Popov via llvm-commits]

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@@ -2537,7 +2537,7 @@ class PHINode : public Instruction {
   /// edges that this phi node will have (use 0 if you really have no idea).
   static PHINode *Create(Type *Ty, unsigned NumReservedValues,
                          const Twine &NameStr = "",
-                         InsertPosition InsertBefore = nullptr) {
+                         InsertPosition InsertBefore = (BasicBlock*)nullptr) {
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nikic wrote:

Why is this necessary despite the `nullptr_t` overload on InsertPosition?

https://github.com/llvm/llvm-project/pull/102608